SECTION CONCRETE PAVING FOR PEDESTRIAN AREAS. A. This Section includes exterior cement concrete pavement for the following:

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1 SECTION CONCRETE PAVING FOR PEDESTRIAN AREAS PART 1 GENERAL 1.1 SUMMARY A. This Section includes exterior cement concrete pavement for the following: 1. Walkways. 2. Courtyards. 3. Plazas. 4. Pedestrian Ramps. 1.2 SUBMITTALS A. Product Data: For each type of product indicated. B. Design Mixtures: For each concrete pavement mixture. C. Related Sections: 1. Section Joint Sealants for expansion joints within pedestrian pavements 1.3 QUALITY ASSURANCE A. Manufacturer Qualifications: Manufacturer of ready mixed concrete products who complies with ASTM C 94/C 94M requirements for production facilities and equipment. B. ACI Publications: Comply with ACI 301, "Specification for Structural Concrete," unless modified by requirements in the Contract Documents. PART 2 PRODUCTS 2.1 STEEL REINFORCEMENT A. Plain Steel Welded Wire Reinforcement: ASTM A 185, fabricated from as drawn steel wire into flat sheets. B. Deformed Steel Welded Wire Reinforcement: ASTM A 497, flat sheet. C. Reinforcing Bars: ASTM A 615/A 615M, Grade 60; deformed. AE Project Number: Concrete Paving

2 D. Plain Steel Wire: ASTM A 82, as drawn. E. Deformed Steel Wire: ASTM A 496. F. Bar Supports: Bolsters, chairs, spacers, and other devices for spacing, supporting, and fastening reinforcing bars, welded wire reinforcement, and dowels in place. Manufacture bar supports according to CRSI's "Manual of Standard Practice." 2.2 CONCRETE MATERIALS A. Cementitious Material: Use[ one of] the following Cementitious materials, of the same type, brand, and source throughout the Project: 1. Portland Cement: ASTM C 150, Type gray. a. Ground Granulated Blast Furnace Slag: ASTM C 989, Grade 100 or Blended Hydraulic Cement: ASTM C 595. B. Normal Weight Aggregates: ASTM C 33, coarse aggregate, uniformly graded. Provide aggregates from a single source. C. Water: ASTM C 94/C 94M. D. Air Entraining Admixture: ASTM C 260. E. Chemical Admixtures: ASTM C 494/C 494M, of type suitable for application, certified by manufacturer to be compatible with other admixtures and to contain not more than 0.1 percent water soluble chloride ions by mass of cementitious material. 2.3 FIBER REINFORCEMENT A. Synthetic Fiber: Polypropylene fibers engineered and designed for use in concrete pavement, complying with ASTM C 1116, Type III, 1/2 to 1 1/2 inches long. 2.4 CURING MATERIALS A. Absorptive Cover: AASHTO M 182, Class 2, burlap cloth. B. Moisture Retaining Cover: ASTM C 171, polyethylene film or white burlap polyethylene sheet. C. Water: Potable. D. Evaporation Retarder: Waterborne, monomolecular film forming; manufactured for application to fresh concrete. AE Project Number: Concrete Paving

3 E. Clear Waterborne Membrane Forming Curing Compound: ASTM C 309, Type 1, Class B, dissipating. F. White Waterborne Membrane Forming Curing Compound: ASTM C 309, Type 2, Class B. 2.5 RELATED MATERIALS A. Expansion and Isolation Joint Filler Strips: ASTM D 1751, asphalt saturated cellulosic fiber or ASTM D 1752, cork or self expanding cork. B. Slip Resistive Aggregate Finish: Factory graded, packaged, rustproof, non glazing, abrasive aggregate of fused aluminum oxide granules or crushed emery with emery aggregate containing not less than 50 percent aluminum oxide and not less than 20 percent ferric oxide; unaffected by freezing, moisture, and cleaning materials. 2.6 CONCRETE MIXTURES A. Prepare design mixtures, proportioned according to ACI 301, with the following properties: 1. Compressive Strength (28 Days): 3000 psi. 2. Maximum Water Cementitious Materials Ratio at Point of Placement Slump Limit: 4 inches, plus or minus 1 inch. 4. Air Content 5 1/2 percent plus or minus 1.5 percent. B. Synthetic Fiber: Uniformly disperse in concrete mix at manufacturer's recommended rate, but not less than 1.0 lb/cu. yd.. C. Color Pigment: Add color pigment to concrete mixture according to manufacturer's written instructions. 2.7 CONCRETE MIXING A. Ready Mixed Concrete: Measure, batch, and mix concrete materials and concrete according to ASTM C 94/C 94M and ASTM C Furnish batch certificates for each batch discharged and used in the Work. PART 3 EXECUTION 3.1 EXAMINATION A. Proof roll prepared sub base surface below concrete pavements with heavy pneumatic tired equipment to identify soft pockets and areas of excess yielding. AE Project Number: Concrete Paving

4 3.2 EDGE FORMS AND SCREED CONSTRUCTION A. Set, brace, and secure edge forms, bulkheads, and intermediate screed guides for pavement to required lines, grades, and elevations. Install forms to allow continuous progress of work and so forms can remain in place at least 24 hours after concrete placement. B. Clean forms after each use and coat with form release agent to ensure separation from concrete without damage. 3.3 STEEL REINFORCEMENT A. General: Comply with CRSI's "Manual of Standard Practice" for fabricating, placing, and supporting reinforcement. 3.4 JOINTS A. General: Form construction, isolation, and contraction joints and tool edgings true to line with faces perpendicular to surface plane of concrete. Construct transverse joints at right angles to centerline, unless otherwise indicated. B. Construction Joints: Set construction joints at side and end terminations of pavement and at locations where pavement operations are stopped for more than one half hour unless pavement terminates at isolation joints. C. Isolation Joints: Form isolation joints of preformed joint filler strips abutting concrete curbs, catch basins, manholes, inlets, structures, walks, other fixed objects, and where indicated. D. Contraction Joints: Form weakened plane contraction joints, sectioning concrete into areas as indicated. Construct contraction joints for a depth equal to at least one fourth of the concrete thickness. If applicable, match jointing of existing adjacent concrete pavement. E. Edging: Tool edges of pavement, gutters, curbs, and joints in concrete after initial floating with an edging tool to a 3/16 inch radius. Repeat tooling of edges after applying surface finishes. Eliminate tool marks on concrete surfaces. 3.5 CONCRETE PLACEMENT A. Moisten sub base to provide a uniform dampened condition at time concrete is placed. B. Comply with ACI 301 requirements for measuring, mixing, transporting, and placing concrete. C. Deposit and spread concrete in a continuous operation between transverse joints. Do not push or drag concrete into place or use vibrators to move concrete into place. D. Screed pavement surfaces with a straightedge and strike off. AE Project Number: Concrete Paving

5 E. Commence initial floating using bull floats or darbies to impart an open textured and uniform surface plane before excess moisture or bleed water appears on the surface. Do not further disturb concrete surfaces before beginning finishing operations or spreading surface treatments. 3.6 FLOAT FINISHING A. General: Do not add water to concrete surfaces during finishing operations. B. Float Finish: Begin the second floating operation when bleed water sheen has disappeared and concrete surface has stiffened sufficiently to permit operations. Float surface with powerdriven floats, or by hand floating if area is small or inaccessible to power units. Finish surfaces to true planes. Cut down high spots and fill low spots. Refloat surface immediately to uniform granular texture. 1. Burlap Finish: Drag a seamless strip of damp burlap across float finished concrete, perpendicular to line of traffic, to provide a uniform, gritty texture. 2. Medium to Fine Textured Broom Finish: Draw a soft bristle broom across float finished concrete surface perpendicular to line of traffic to provide a uniform, fine line texture. 3. Medium to Coarse Textured Broom Finish: Provide a coarse finish by striating floatfinished concrete surface 1/16 to 1/8 inch deep with a stiff bristled broom, perpendicular to line of traffic. C. Slip Resistive Aggregate Finish: Before final floating, spread slip resistive aggregate finish on pavement surface according to manufacturer's written instructions. 1. Cure concrete with curing compound recommended by slip resistive aggregate manufacturer. Apply curing compound immediately after final finishing. 2. After curing, lightly work surface with a steel wire brush or abrasive stone and water to expose nonslip aggregate. 3.7 CONCRETE PROTECTION AND CURING A. General: Protect freshly placed concrete from premature drying and excessive cold or hot temperatures. B. Comply with ACI for cold weather protection. C. Evaporation Retarder: Apply evaporation retarder to concrete surfaces if hot, dry, or windy conditions cause moisture loss approaching 0.2 lb/sq. ft. x h before and during finishing operations. Apply according to manufacturer's written instructions after placing, screeding, and bull floating or darbying concrete, but before float finishing. AE Project Number: Concrete Paving

6 D. Begin curing after finishing concrete but not before free water has disappeared from concrete surface. E. Curing Methods: Cure concrete by moisture curing, moisture retaining cover curing, curing compound, or a combination of these methods. 3.8 PAVEMENT TOLERANCES A. Comply with tolerances of ACI 117 and as follows: 1. Elevation: 1/4 inch. 2. Thickness: Plus 3/8 inch, minus 1/4 inch. 3. Surface: Gap below 10 foot long, unleveled straightedge not to exceed 1/4 inch. 4. Joint Spacing: 3 inches. 5. Contraction Joint Depth: Plus 1/4 inch, no minus. 6. Joint Width: Plus 1/8 inch, no minus. 3.9 REPAIRS AND PROTECTION A. Remove and replace concrete pavement that is broken, damaged, or defective or that does not comply with requirements in this Section. B. Protect concrete from damage. Exclude traffic from pavement for at least 14 days after placement. C. Maintain concrete pavement free of stains, discoloration, dirt, and other foreign material. Sweep concrete pavement not more than two days before date scheduled for Substantial Completion inspections. END OF SECTION AE Project Number: Concrete Paving